1. Field of the Invention
This invention relates to improvements in seed drill apparatus and more particularly, but not by way of limitation, to a seed drill having cooperating seed disc means for preparing a seed receiving groove in the earth, whether or not the surface of the ground has been plowed or otherwise previously prepared for planting.
2. Description of the Prior Art
The opening of ruts or longitudinally extending grooves in the surface of the earth for planting of seeds therein is an old and well known planting procedure. The usual or standard procedure in widespread use today includes the preparing of the ground or earth by plowing, tilling, or the like, prior to the seed planting operation. Seed drill apparatus comprising a plurality of earth penetrating discs disposed in spaced, side-by-side relation for producing the seed receiving grooves is frequently utilized, and the discs provided on the present day seed drills normally penetrate or open the earth in relatively narrow slits with substantially straight or vertically disposed, longitudinally extending sidewalls. In some instances, the discs are disposed in a tandem arrangement wherein the leading disc initially opens the groove, and the trailing disc widens the initial groove for facilitating the depositing of seeds in the groove. For example, a Defense Publication of Koronka et al., No. 777,309, shows the use of two discs, with the first disc being a slit cutting disc for initially opening the seed receiving groove and the second disc serving to widen the initial slit for facilitating the depositing of the seeds in the groove. Another seed drill apparatus is shown in the Coulter U.S. Pat. No. 4,289,081 wherein two discs are mounted in tandem relation, but the point of rotation of the discs is offset from each other due to relatively close physical relation between the discs. The Bailey U.S. Pat. No. 4,214,537 relates to a seed drill having a plurality of discs arranged in a row, with the discs being angled toward each other. These devices have certain disadvantages, however, in that the usual cross sectional configuration of the seed receiving groove is usually such that the depositing of the seeds at the center or bottom of the groove may be difficult and somewhat uncontrolled. In addition, the present day seed drill devices normally require that the ground be plowed, tilled, or the like, prior to the use of the apparatus for preparing the seed receiving grooves.